Power-driven rotary brush for cleaning the rolls of a rolling mill



Oct. 31, 1967 c. E. SMITH ETAL 3,349,420 POWER-DRIVEN ROTARY BRUSH FORCLEANING THE v ROLLS OF A ROLLING MILL Filed Feb. 25, 1966 3Sheets-Sheet l I nventor YRIL EDWIN SMITH A itorne y JOHN AND E T W%Z7Oct. 31, 1967 c E. SMITH ETAL. 3,349,420

POWER-DRIVEN f OTARY BRUSH FOR CLEANING THE ROLLS OF A ROLLING MILLFiled Feb. 23, 1966 5 Sheets-Sheet 2 Inventor QYRIL EDWIN SMITH JOHNANDRE TRACY Attorney Oct.- 31, 1967 c. E. SMITH ETAL 3,349,420

POWER-DRIVEN ROTARY BRUSH FOR CLEANING THE ROLLS OF A ROLLING MILL FiledFeb. 23, 1966 5 Sheets-Sheet 5 Invenlor CYRIL EDWIN SMITH JOHN ANDRETRACY A Home y United States Patent 3,349,420 POWER-DRIVEN ROTARY BRUSHFOR CLEANING THE ROLLS OF A ROLLING MILL Cyril E. Smith, Ringwood, andJohn Andre Tracy, Bournemouth, England, assignors to The LoewyEngineering Company Limited, Bournemouth, England, a company of GreatBritain Filed Feb. 23, 1966, Ser. No. 529,483 Claims priority,application Great Britain, Feb. 22, 1965, 7,640/ 65 4 Claims. (Cl. 1521)This invention relates to power-driven rotary brushes for cleaning therolls of rolling mills.

In certain types of rolling mills, it is necessary for the surfaces oftheir working rolls to be kept clean during the rolling operation, sothat the articles produced on these mills are free from surfaceblemishes. This require? ment exists, in particular, in the case ofrolling mills which produce thin metal strip, such as foil.

It has been proposed to provide for this purpose powerdriven rotarybrushes which were a permanent attachment to the mill and could thus bemade to contact the working rolls of the mill during a rollingoperation. These brushes consisted essentially of a rotary drum whichwas mounted at its ends on stationary journals supported in a framewhich was adapted to be moved towards and away from a working roll. Theoutside of the drum was covered with bristles of steel wire which, bythe to and fro movements of the drum, were moved into and out ofengagement with the surface of an associated working roll.

The rotary power-drive for the drum was built into the latter andconsisted of an electric squirrel-cage motor. The space foraccommodating this motor was determined by the internal diameter of thedrum, which, for practical reasons, had to be kept within certainlimits. A limited number of poles could therefore only be provided onthe motor, and its speed was therefore correspondingly high. It was thusnecessary to arrange a reduction gear inside the drum and between motorand drum. Furthermore, the motor had to be protected against water,scale and dirt due to its location in the immediate proximity of themill. Thus, the motor had to be of the fully-enclosed type, and the sizewas thereby increased. The result of these contradictory requirementswas a motor of relatively small diameter and great length. Such a motorhad to be specially designed and built and was therefore expensive.

The known brushes were further adapted to make rapid short-strokeoscillations in the axial direction of the drum, in order to intensifythe brushing effect. To this end, there was built into the drum aspecial drive which translated the rotary movement of the motor into anoscillating one.

It is an object of the present invention to provide an improvedpower-driven rotary brush for cleaning the rolls of rolling mills.

In the brush according to the invention, the rotary power-drive consistsof a built-in hydraulic motor of the im eller type.

Such a motor is particularly suitable for this application, since itrequires much less space than an electric motor, so that it is possibleto accommodate, within a given diameter of a drum, a hydraulic motor ofnormal design for the power in question. Furthermore, the motor isself-cooling, and no extra cooling means need be provided. The hydraulicmotor may be regulated from the outside over a very wide range ofspeeds, so that a reduction gear mounted within the drum, which wasnecessary in the case of an electric motor, may be simplified oromitted. Finally, the speed can be steplessly regulated from theoutside.

3,349,420 Patented Oct. 31, 1967 According to a feature of theinvention, an improved mechanism is provide for effecting axialoscillating movement of the drum during rotation thereof.

In order that the invention may be more readily understood, oneembodiment of a power-driven rotary brush will now be described withreference to the accompanying drawings, in which:

FIGURE 1 is a longitudinal section of the end of the brush whichcontains the hydraulic motor;

FIGURE 2 is a longitudinal section of the opposite end of the brush ofFIGURE 1 which contains the axial oscillating mechanism; and

FIGURE 3 is a longitudinal section on the line 3-3 in FIGURE 1.

The brush shown in the drawings consists basically of a cylindrical drum1, the outer surface of which is covered with bristles 2 of steel wire.The drum 1 is rotatably mounted on stationary, i.e. non-rotatable,journal or stub shafts 3 and 4 (see FIGURES 1 and 2 respectively) whichproject from opposite ends of the drum 1, and, when the brush is in use,are supported in a frame (not shown) which is movable towards and awayfrom a working roll to be cleaned (not shown) to bring the bristles 2into and out of engagement with the surface of this working roll.

As shown in FIGURES 1 and 3, the drum 1 is driven by a built-inhydraulic motor 5 having a stationary housing connected to the inner endof the stationary shaft 3 by a spacer block 6, and located in a frame 7which is also secured to the spacer block 6. Any suitable type ofimpeller motor may be used, for example, a motor having twisted vanes,and in this embodiment, the motor 5 is a Lucas I.M.H. 500 hydraulicmotor, which is capable of operating over a speed range of 200 to 2000revolutions/minute when supplied with hydraulic fluid at a pressure of2000 pounds/square inch, and a flow rate of 1.65 to 16.5 gallons/minute.The hydraulic fluid under pressure is fed to and removed from, the motor5, through a number of passages 8 extending from an external adapter 9(shown in broken lines), through the shaft 3 and spacer block 6 andconnected to the motor 5 by means of a manifold 10 (FIGURE 3). A sump(not shown) may be provided within the drum 1 to collect and drain anyhydraulic fluid leaking from the motor 5.

The motor 5 is provided with a drive shaft 11 which rotates the drum 1through a reduction gear train comprising a pinion 12 secured to thedrive shaft 11, which meshes with a pair of idler gears 13 rotatableabout stationary shafts 14 (see FIGURE 3) carried by the frame 7. Theidler gears 13 mesh with an internally toothed ring 15 which, as shownin FIGURE 3, is coupled to the drum 1 by means of keys 16 which areslidable in longitudinally extending keyways 17 cut in the internalsurface of the drum 1, so that axial but not rotation movement may takeplace between the ring 15 and drum 1. i

The drum 1 is rotatably supported, at its end containing the motor 5, bymeans of roller bearings =18 arranged between the ring 15 and frame 7,and roller bearings 19 arranged between the shaft 3 and a bearing ring20 which .is keyed at 21 to the drum 1. Sealing means 22 are provided oneach side of the bearings 18 and 19 to prevent contamination.

As previously mentioned, the end of the drum 1 opposite to thatcontaining the hydraulic motor 5 contains a mechanism foraxiallyoscillating the drum 1, and this mechanism will now be described withreference to FIG- URE 2. As shown in this figure, the stationary shaft 4is axially slidable telescopically within an inner sleeve '23. Thissleeve 23 is keyed to the shaft 4 so that it is axially slidable, butnot rotatable, relative to this. shaft, and carries a pair of axiallyspaced roller bearings 24 ro- 3 tatably supporting an outer sleeve 25rigidly secured within the drum 1.

Rigidly mounted by its casing at the inner end of the inner sleeve 23 isa speed reduction unit 26, for example, a Heliocentric speed reductionunit having a ratio of 80: 1. The input shaft 27 of this unit 26 isnonrotatably coupled via a flexible universal coupling 28 to atransverse flange 29 rigid with the internal surface of the drum 1. Theoutput shaft 30 of the unit 26 is keyed to a boss 31 to which is clampeda ring 32 provided with a pair of radially projecting lugs 33 betweenwhich is mounted one end of a link member 34. The opposite end of thelink member 34 is secured between a pair of longitudinally projectinglugs 35 offset axially from the output shaft 30, and carried by a stubaxle 36, freely rotatable, but axially located, relative to the shaft 4in roller bearing 37.

As shown in the drawings, each end of the drum 1 is provided with an endplate 38 incorporating a seal 39 which seals against its associatedshaft 3 or 4, preventing entry of scale, dirt or other extraneousmaterials into the space within the drum.

In operation, hydraulic fluid under pressure is supplied to andwithdrawn from the motor 5 through the passages 8 and manifold 10causing the motor drive shaft 11 to rotate. This rotation is transmittedvia the reduction gear train comprising the pinion 12, idler gears 13and internally toothed ring 15 keyed to the drum 1, to rotate the drumon the roller bearings 18, 19 and 24 around the stationary shafts 3 and4 and the drive and oscillating V mechanisms. The speed of the motor maybe regulated continuously from outside the drum by varying the pressureof the hydraulic fluid, so as to give a wide range of drum speeds, forexample, from 77 to 770 revolutions/ minute, without changing the ratioof the reduction gear train. Such a speed range gives, with an 11 inchexternal diameter drum carrying bristles bringing the overall diameterto 15 inches, a surface speed of between 302 and 3020 feet/minute. Thehydraulic fluid serves the added purpose of cooling the motor 5,eliminating the need for additional cooling fans.

Rotation of the drum 1 is transmitted, via the transverse flange 29 anduniversal coupling 28, to the input shaft 27 of the speed reduction unit26, resulting in slow rotation of the output shaft 30, and therefore ofthe lugs 33 and link member 34 bodily about the output shaft 30. Due tothe eccentric arrangement of the lugs 35 relative to the axis of theoutput shaft 30, this rotation causes the unit 26, and therefore theinner sleeve 23, outer sleeve 25, and therefore the drum 1, toreciprocate or oscillate axially relative to the stationary shaft 4between the positions shown in full and broken lines at the left handends of FIGURE 1. This oscillatory motion is accommodated at the otherend of the drum, since the rings 15 and are keyed to, and thereforeaxially slidable relative to, the drum 1.

We claim:

1. A power driven rotary brush for cleaning the surface of a workingroll in a rolling mill, comprising a drum, provided with bristles aroundits external surface, and rotatable about, and axially slidable relativeto, a pair of stationary stub shafts extending one into each end of thedrum, a hydraulic motor of the impeller type being mounted within thedrum and adapted to rotate the drum relative to the stationary stubshafts, said hydraulic motor being rigidly mounted by its casing at theinner end of one stub shaft and being provided with an output shaftcoupled to the drum through a reduction gear train including aninternally toothed gear ring keyed to the drum to prevent rotationbetween the drum and gear ring but to permit axial movementtherebetween, and means for oscillating the drum axially relative to thestub shafts upon rotation of the drum being connected to the other ofsaid stub shafts, said oscillating means including a sleeve mounted foraxial movement, but not rotation, on and relative to the inner end ofsaid other shaft, and rotatable but not axially movable relative to thedrum, and drive means for producing axial oscillatory motion betweensaid other shaft and said sleeve upon rotation of the drum.

2. A brush as claimed in claim 1, wherein the drive means comprises aspeed reduction unit having a housing supported by and stationary withrespect to the sleeve. an input shaft coupled to the drum for rotationtherewith, and an output shaft having a radially displaced couplingelement rotatable therewith, the coupling element being rotatablyconnected by an inclined link member to the said other shaft at aposition displaced from the axis of rotation of the output shaft.

3. A power driven rotary brush for cleaning the surface of a work rollof a rolling mill, including a hollow elongate cylindrical metal drum, alayer of steel wire bristles secured to and surrounding the drum, afirst nonrotatable stub shaft extending into one end of the drum andcarrying within the drum a longitudinally extending frame, first andsecond axially spaced rings each disposed within and keyed to the drumto permit axial but not rotational movement between each ring and thedrum, bearing means between the first ring and the first stub shaft andbetween the second ring and a zone of the frame axially remote from thefirst stub shaft, said bearing means permitting rotational butpreventing axial movement of the rings relative to the first stub shaftand frame, a hydraulic motor of normal design mounted immovably by itshousing in the frame, and having a drive shaft coupled via simplereduction gear train to drive the second ring, stationary hydraulicfluid inlet and outlet passages extending from outside the drum,longitudinally through the first stub shaft and at their inner endsconnected to the hydraulic motor, a second stationary stub shaftextending into the opposite end of the drum, a sleeve surrounding theinner end of the second stub shaft, mounted for axial telescopic but notrotational movement relative to the second stub shaft, axially spacedbearing means between said sleeve and the opposite end of the drum,permitting rotational but not axial movement between the drum andsleeve, and oscillatory means interconnecting the sleeve and second stubshaft adapted to axially reciprocate the sleeve relative to the secondstub shaft upon rotation of the drum relative to the first and secondstub shafts by the hydraulic motor.

4. A brush as claimed in claim 3, wherein said oscillating meanscomprises a speed reduction unit including a casing fixedly secured tothe inner end of the sleeve and an input shaft, rotatable about an axiscoincident with the axis of rotation of the drum, coupled to androtatable with the drum, and an output shaft rotatable about the sameaxis, carrying a radial extension, and an inclined link member pivotallyconnected at one end to said radial extension and at its opposite endpivotally connected to a stub axle freely mounted in the inner end ofsaid second stub shaft for rotation about a longitudinal axiseccentrically olfset from the axis of the output shaft, but axiallyfixed relative to said second stub shaft.

References Cited UNITED STATES PATENTS 3,113,332 12/1963 Kasper 15-823,178,744 4/ 1965 Christian 15-2l 3,238,550 3/1966 Christian 15--2lCHARLES A. WILLMUTH, Primary Examiner.

E. L. ROBERTS, Assistant Examiner.

1. A POWER DRIVEN ROTARY BRUSH FOR CLEANING THE SURFACE OF A WORKINGROLL IN A ROLLING MILL, COMPRISING A DRUM, PROVIDED WITH BRISTLES AROUNDITS EXTERNAL SURFACE, AND ROTATABLE ABOUT, AND AXIALLY SLIDABLE RELATIVETO, A PAIR OF STATIONARY STUB SHAFTS EXTENDING ONE INTO EACH END OF THEDRUM, A HYDRAULIC MOTOR OF THE IMPELLER TYPE BEING MOUNTED WITHIN THEDRUM AND ADAPTED TO ROTATE THE DRUM RELATIVE TO THE STATIONARY STUBSHAFTS, SAID HYDRAULIC MOTOR BEING RIGIDLY MOUNTED BY ITS CASING AT THEINNER END OF ONE STUB SHAFT AND BEING PROVIDED WITH AN OUTPUT SHAFTCOUPLED TO THE DRUM THROUGH A REDUCTION GEAR TRAIN INCLUDING ANINTERNALLY TOOTHED GEAR RING KEYED TO THE DRUM TO PREVENT ROTATIONBETWEEN THE DRUM AND GEAR RING BUT TO PERMIT AXIAL MOVEMENTTHEREBETWEEN, AND MEANS FOR OSCILLATING THE DRUM BEING CONNECTED TO THEOTHER UPON ROTATION OF THE DRUM BEING CONNECTED TO THE OTHER OF SAIDSTUB SHAFTS, SAID OSCILLATING MEANS INCLUDING A SLEEVE MOUNTED FOR AXIALMOVEMENT, BUT NOT ROTATION, ON AND RELATIVE TO THE INNER END OF SAIDOTHER SHAFT, AND ROTATABLE BUT NOT AXIALLY MOVABLE RELATIVE TO THE DRUM,AND DRIVE MEANS FOR PRODUCING AXIAL OSCILLATORY MOTION BETWEEN SAIDOTHER SHAFT AND SAID SLEEVE UPON ROTATION OF THE DRUM.